Many types of control means for controlling the operation of emergency valves in a liquid storage tank of a transport vehicle, including remote control of the emergency valve, are known in the art. Canadian Pat. No. 684,134 issued Apr. 14, 1964 to Applicant and entitled "Cascade Emergency Valve" discloses an emergency valve which is operated from a remote location by means of a cable or cord. U.S. Pat. No. 2,600,977 issued June 17, 1952 to Applicant discloses an emergency valve system for a gasoline transport truck, which is remotely controlled, utilizing compressed air tapped from a manually operated pump disposed in a cabinet on the vehicle. U.S. Pat. No. 3,190,551 issued Oct. 7, 1975 to Applicant discloses a remote control, internal emergency valve for the outlet of a transportation storage tank, operable by compressed air.